And it's very Linux-like, very much so. It's got free bsd unix, which is the same as Linux.

它与Linux非常非常类似。它有免费的bsd unix，这一点和Linux一样。

In unix, we can call " cat" - short for concatenate.

在 unix 中，我们可以称其为“cat”——concatenate 的缩写。

Find is the tool that, pretty much comes with every UNIX system.

Find 是几乎每个 UNIX 系统都附带的工具。